Questions about the use of built-in Mathematica functions, including pure functions.
1
vote
1answer
26 views
0
votes
0answers
32 views
Editing the function argument
I'd like to construct a function, that changes its own input. The code
...
0
votes
0answers
20 views
How to change the formulae of FeatureExtraction?
I have a feature extraction function fe, which gives me n/0.816497 as the output of fe[{1}]:-
...
1
vote
2answers
62 views
Issue with the use of Position
Reading the documentation of Position, I found there's a possible issue:
Position looks for matches based on patterns, which may ...
0
votes
0answers
31 views
Laurent Expansion: Poles of Symbolic Form [on hold]
I am trying to use Mathematica in order to obtain the Laurent expansion of a function $f(z)$ the poles of which are functions of three variables, $q$, $m$ and $t$: $g(q,t,m)$. To specify, my function ...
4
votes
1answer
47 views
Solve/Reduce not working on a function with a condition/domain restriction?
I'm working with a trigonometric function, so I thought it would be convenient to set a condition to restrict the domain so I wouldn't have to specify it in the solve function each time. Here is a ...
-1
votes
0answers
24 views
How to force FeatureExtraction to extract specific number of features?
I have two FeatureExtraction functions as below:-
...
1
vote
0answers
91 views
Solve differential equation
I want to solve the next differential equation,
fun = t^2*x''[t] + 4/3*t*x'[t] - 2/3*(1 - (L^2)/(6*t^(2/3))) x[t] - (2*L^2)/(45*t^(2/3)) == 0
DSolve[fun, x, t]
...
1
vote
3answers
58 views
Evaluating a function that takes numerical arguments over a given list/table
I have a given list of some numbers e.g.
a = {0, 0.233, 0.65, 1.56};
I want to evaluate a function
...
1
vote
1answer
20 views
Defining dynamic limit for a list plot
Helly everybody,
I will try to keep this as simple as possible.
I have a function which looks like this:
Min[T_, E_, D_] := Module[ ..... List = {...} ];
In ...
1
vote
0answers
68 views
inequalitysolution [closed]
I have a function for which I would like to solve an inequality and find a range of r with respect to other quantities. I am not well familiar with Mathematica, ...
0
votes
1answer
38 views
Arbitrary conditional multivariate expectation
I am interested in finding a conditional expectation of a multivariate Normal distribution. For example, let $X$ and $Y$ denote two random variables with a joint normal distribution.
Let $X \sim N(\...
0
votes
1answer
54 views
Limit of a complex function - Output=input
I'm trying to compute the following limit:
Limit[ (E^(I t w)) /(2 (-I + 1)), t -> Infinity]
but Mathematica does not compute it. The above limit does not ...
6
votes
5answers
265 views
Does Mathematica have a twin prime equivalent of `PrimePi`?
Well, it's all there in the title! I'd like to be able to plot the number of twin primes =<x. Is there an inbuilt function that can do this?
-1
votes
0answers
101 views
Smart Replacement in Mathematica [closed]
I'm working on a project to replicate the derivation of the optical Bloch Equations in Mathematica and this part has me stumped. I'm trying to transform the solutions to the coupled ODE's into a ...
0
votes
1answer
30 views
Function of a function using SphericalPlot3D
If anyone has any idea how to turn all of that plotting stuff (hcpii4plot) into a function which takes hcpii4angfunc[θ, ϕ] as an ...
1
vote
1answer
42 views
ListPlot as a function of a variable
I was writing the following code. Now I am a bit stuck with a problem. Can anyone help?
My code lies below:
...
0
votes
0answers
33 views
Functions definitions with variable arguments
How do you define a variable amount of functions with a variable amount of arguments? I don't get the reference at all :
...
3
votes
1answer
38 views
1
vote
0answers
20 views
Defining a symbolic function on a list of inputs [solved, but the reason is unclear] [duplicate]
The following MWE should give a symbolic function (is this the correct terminology?) f, defined on the entries of some list list....
4
votes
2answers
40 views
Why application of “Reap” in the forms of prefix and suffix does not work? [duplicate]
I have been believing in Wolfram language that several forms of application of a function are equivalent:
f[a]
f@a
a//f
a~f~b (*for more than one argument*)
But ...
4
votes
1answer
39 views
Confusion with function “InverseFunction”
Run codes below
InverseFunction /@ {InverseFunction, List, Reverse, RotateLeft, RotateRight, Sequence}
and one is returned with
...
1
vote
1answer
29 views
Diagonal Matrix of a Piecewise Function
I have a piecewise function now I want to do a Matrix operation on it. How can I do that?
For example, the Function is like below:
...
0
votes
0answers
3 views
What will be the output of the following math [migrated]
a+b=ab=a^2-b^2
(1+\sqrt{5})/2
2.(3+\sqrt{5})/2
2
/sqrt{5}
not sure at all how to find the answer.
I tried a=ab/b and a=(a^2-b^2)/b but after that I am lost
3
votes
3answers
157 views
InverseFunction fails to invert $e^{-x/2}-e^{x/2}$
I need to invert a function. I want to isolate the x basically. By the looks of the graphic I plotted, the function seems to be invertible, however when I call <...
1
vote
2answers
134 views
Integration of a function that oscillates rapidly (apparently)
I would like to know if you could help me solve some doubts about the integration of a function that oscillates rapidly (apparently) that depends on time and two angular variables. The parameters S ...
2
votes
3answers
74 views
Function of a function, both of a list of variables
I am trying to avoid dealing with long explicit lists of variables.
What i do so far is the following:
VarList={x_, y_};
ParList={x, y};
ValList={2, 3};
What ...
5
votes
1answer
189 views
Applying a Function within a Function
How do I define a function with a function?
Ok, so lets take a positive integer n and output the result iteratively summing and squaring the integers from 1 to n...
...
0
votes
0answers
38 views
0
votes
1answer
43 views
0
votes
0answers
47 views
Is there a way to Connect a function ''normally'' through its Pole?
Basicaly I have this function:
...
3
votes
1answer
40 views
How to retrieve values of a function from a file
I defined the following function:
q5e8[z_?NumericQ] := q5e8[z?NumericQ] = NIntegrate[Sin[(2 5 10^8 - v) z]/z^5,
{v, 0.1, 2 5 10^8}]
As you can see, it is a ...
6
votes
2answers
114 views
How to create non-rectangular array with Array?
From the answers to this question, I learned that the recommended way to construct a symbolic sum of terms in an expression is to use Array.
But I'm having a ...
0
votes
1answer
48 views
How do I apply my function to my list of arguments? [closed]
I have a list of integers
l := {3, 5, 7}
and a function
f1[a_] := a + 1
I would like to apply ...
2
votes
1answer
78 views
How can I find the numerical value of the limit of more complex expressions?
Sometimes when trying to find the limit of a function $f(n)$ when $n\to\infty$ using Limit[f,n->Infinity], it seems that Mathematica is unable to compute it ...
1
vote
1answer
53 views
Non-neural-network version of SoftmaxLayer[]
Is there an built-in normalized exponential function (a.k.a. Softmax), equivalent to SoftmaxLayer[] but usable outside neural networks?
For example, the function would go from {1, 2, 3, 4, 1, 2, 3} ...
0
votes
2answers
20 views
Numerical output using Select and FactorInteger
I have concocted a function from other peoples examples to find the powers of two in a prime decompostion, in the example below its $2^2=4$ gives {2,2}.
...
1
vote
1answer
31 views
Evaluate a function with vectors and return matrix
I have a matrix given as a function of is indices and another free parameter as follows
A[x_, i_, j_] = x*i*j
Now I would like to evaluate this for a given ...
1
vote
0answers
36 views
Finding the mathematical function is plotted by using the bodeplot command
I've the following code:
...
1
vote
1answer
26 views
Part of domain not being plotted in Show
I am exploring Euler's product formula for the Riemann Zeta function but I have come across a problem plotting functions with various terms of accuracy. My code is ...
7
votes
2answers
112 views
Constructing expressions using Sum vs Array[… Plus] vs Plus@@Table[…]
For constructing a sum of terms which are symbolic, I noticed that in addition to
...
0
votes
0answers
51 views
How to give a function multiple variables in a mapped and nested list?
I come from python (not advanced tho), and have been learning mathematica. I'm currently struggling with the following code:
This is a basic version of what i wanted to implement:
...
1
vote
1answer
31 views
1
vote
0answers
31 views
Calculate with general discrete probability functions?
I would like to work with a discrete probability function $P[x\_]$ that only has the property that it is defined for $x\geq0$, such that
Sum[P[x],{x,0,Infinity}]
...
0
votes
0answers
16 views
Plotting a function on a complex plane [duplicate]
I am new to Mathematica and I would like to know how to plot a complex function, say $f(z) = \frac{-z}{z^2 - 1}$ for $|z|<1$?
2
votes
0answers
39 views
How to store the values of a function in a file
As it is well known, it is possible to define a function that remembers its values once its evaluated, using the following code:
f[x_]:=f[x]=rhs
During the day I evaluate f[x], for many x's, and I ...
3
votes
0answers
40 views
Conditional application of a function (looking for a built-in solution)
Is there a built-in function which will apply a function f to x when test yields true? A ...
1
vote
1answer
26 views
Calculating a parametrized maximum, as a function of the parameter
Suppose I have the following maximization problem:
Maximize[{x^2-a,0<=x<=a},{x}]
The result is a function of $a$:
I want to extract this function of $a$. ...
2
votes
4answers
89 views
Position in the list after a using a function
I want to generate a list after using a function. In this list the original position is important.
...
0
votes
2answers
42 views
Plotting a function while varying a variable (on the x-axis) using two formulas [duplicate]
I want to plot the following function, where Rb is the variable (that has to be on the x-axis):
...
